A simple and inexpensive molecular method for sexing and identification of the forensic samples of elephant origin

The population of the Asian elephant is being dramatically reduced due to poaching of the ivory from the male. As poaching occurs in remote forests, it often takes weeks or longer for it to be discovered and it is therefore often very difficult to determine the sex of the decomposed body. Data suggest that in the recent past, over 2000 male elephants have been poached in South India. We have developed a technique based on molecular markers to determine that the carcass is an elephant and that it is a male. Using DNA sequence information from Genbank, we have developed two primer pairs: one for the mitochondrial DNA (mtDNA) and the other for the sex-determining region of Y chromosome (SRY) gene of the Indian elephant. After PCR amplification of known elephant DNA, we found that the mtDNA was common in both males and females, whereas the SRY-specific amplicon was observed only in the male.     

Y chromosome STR haplotypes and allele frequencies in Illinois Caucasian, African American, and Hispanic males

POPULATION: Population: Illinois Caucasian ( n =117), Illinois African American ( n =218), and Illinois Hispanic ( n =68).     

Alpha-amylase kinetic test in bodily single and mixed stains

Recently, in Italy, a murder and a putative sexual violence was accomplished on a child. A bodily fluids mixture on the child's underwear between the victim (female) and the suspect (male) was ascertained by short tandem repeat (STR) DNA typing and, due to the absence of seminal fluid, saliva from the suspect and urine from the child was hypothesized. In order to investigate the possibility of specifically and rapidly detecting saliva stains both alone and mixed with other bodily fluids, we used a quantitative spectrophotometric technique, named Amylase test, for the detection of alpha-amylases. We determined alpha-amylase activity and reaction kinetic curves in several samples collected from the child's underwear. In order to confirm our intuition, we first tested saliva, perspiration, and urine, singularly and in mixtures; second, several forensic stains including saliva, perspiration, urine stains, saliva/perspiration, and saliva/urine mixture stains were tested. Evaluating alpha-amylase activity values and time-course curves' behavior of alpha-amylase reactions we were able to recognize successfully, in all cases, the presence of saliva and to distinguish it specifically from other bodily fluids containing alpha-amylase. A further confirmation of our result was provided by STR DNA typing on several areas of the underwear: a clear correlation between alpha-amylases activity and male DNA was detected on all the samples evaluated.     

DNA芯片分析单核苷酸多态性及其法医学应用

DNA芯片技术作为一门新兴的高科技生物技术,显示了它旺盛的生命力和迅猛的发展势头。单核苷酸多态性(SingleNucleotidePolymorphisms,SNPs)是最常见的人类基因组变异类型。它作为一种有效的人类遗传标记,在疾病相关性研究、药物基因组学、法医学、人类进化和迁移等研究中发挥了重要作用。它同DNA芯片技术结合运用也将在法医检验,尤其是亲子鉴定和个人识别中发挥重要作用。本文主要讨论了DNA芯片和SNPs的特点,以及二者联合运用于法医学的价值。     

性染色体及线粒体DNA遗传标记的法医学应用

对性染色体及线粒体DNA的结构特征、遗传特征等相关基础知识及其遗传标记在法医学领域应用的研究进展等进行了综述,分析了上述各类遗传标记在法医学领域应用的利弊,以促进非常染色体DNA遗传标记在法医学实践中的应用。